323 has_many :through => belongs_to_association bug

I updated the patch for 323 to work with the most recent Rails (it
fixes a bug in has_many :through functionality).

http://rails.lighthouseapp.com/projects/8994-ruby-on-rails/tickets/323-has_many-through-belongs_to_association-bug#ticket-323-18

Please review and commit if possible. Thanks,

Zach Dennis
http://www.continuousthinking.com
http://www.mutuallyhuman.com